Ash vacuum and separator with filter cleaning device

ABSTRACT

A vacuum system includes a filter cleaning mechanism which allows the filter to be cleaned without removal from the vacuum. This mechanism can include a carrying handle which is biased against the lid by a spring. The handle may be released from a vertical position, causing the handle to forcefully strike the lid and dislodge debris from the filter. The vacuum may include a spark arrestor disposed around the filter. The spark arrestor encloses the filter and surrounds the filter sides with a metal screen. The spark arrestor has holes formed in the bottom around the outer perimeter of the filter so that debris which is dislodged from the filter falls through the holes and into the vacuum canister.

PRIORITY

The present application claims the benefit of U.S. ProvisionalApplication Ser. No. 61/747,942, filed Dec. 31, 2012 and U.S.Provisional Application Ser. No. 61/817,749, filed Apr. 20, 2013, bothof which are herein incorporated by reference in their entirety.

THE FIELD OF THE INVENTION

The present invention relates to vacuum cleaners. More specifically, thepresent invention relates to a system for cleaning the filters on vacuumcleaners and vacuum separation canisters.

BACKGROUND

Canister style vacuums have become quite common. They are frequentlyused in both residential and industrial applications. Canister vacuumsmay be used for vacuuming cars, cleaning in shops and garages, capturingdust from tools, cleaning fireplace ash, etc. Canister vacuums oftenhave a pleated cylindrical filter inside of the debris canister. Largedebris is deposited into the canister while dust is separated from theair by the filter.

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting and non-exhaustive examples of the present invention aredescribed with reference to the following figures, wherein likereference numerals refer to like parts throughout the various viewsunless otherwise specified.

FIG. 1 shows a perspective drawing of a vacuum according to someembodiments of the present disclosure.

FIG. 2 shows another perspective drawing of the vacuum of FIG. 1.

FIG. 3 shows a perspective drawing of a portion of the vacuum of FIG. 1.

FIG. 4 shows a perspective drawing of a portion of the vacuum of FIG. 1.

FIG. 5 shows a perspective drawing of a portion of the vacuum of FIG. 1.

FIG. 6 shows another perspective drawing of the vacuum of FIG. 1.

FIG. 7 shows another perspective drawing of the vacuum of FIG. 1.

FIG. 8 shows a perspective drawing of the vacuum of FIG. 1 having avacuum motor attached thereto.

FIG. 9 shows a drawing of portions of the vacuum of FIG. 8.

FIG. 10 shows a drawing of portions of the vacuum of FIG. 8.

FIG. 11 shows a drawing of portions of the vacuum of FIG. 8.

FIG. 12 shows a drawing of portions of the vacuum of FIG. 8.

FIG. 13 shows a drawing of portions of the vacuum of FIG. 8.

Corresponding reference characters indicate corresponding componentsthroughout the several views of the drawings. Skilled artisans willappreciate that elements in the figures are illustrated for simplicityand clarity and have not necessarily been drawn to scale. For example,the dimensions of some of the elements in the figures may be exaggeratedrelative to other elements to help to improve understanding of variousexamples of the present invention. Also, common but well-understoodelements that are useful or necessary in a commercially feasibleembodiment are often not depicted in order to facilitate a lessobstructed view of these various embodiments of the present invention.

It will be appreciated that the drawings are illustrative and notlimiting of the scope of the invention which is defined by the appendedclaims. The examples shown each accomplish various different advantages.It is appreciated that it is not possible to clearly show each elementor advantage in a single figure, and as such, multiple figures arepresented to separately illustrate the various details of the examplesin greater clarity. Similarly, not every example need accomplish alladvantages of the present disclosure.

DETAILED DESCRIPTION

In the following description, numerous specific details are set forth inorder to provide a thorough understanding of the present invention. Itwill be apparent, however, to one having ordinary skill in the art thatthe specific detail need not be employed to practice the presentinvention. In other instances, well-known materials or methods have notbeen described in detail in order to avoid obscuring the presentinvention.

Reference throughout this specification to “one embodiment”, “anembodiment”, “one example” or “an example” means that a particularfeature, structure or characteristic described in connection with theembodiment or example is included in at least one embodiment of thepresent invention. Thus, appearances of the phrases “in one embodiment”,“in an embodiment”, “one example” or “an example” in various placesthroughout this specification are not necessarily all referring to thesame embodiment or example. Furthermore, the particular features,structures or characteristics may be combined in any suitablecombinations and/or sub-combinations in one or more embodiments orexamples. In addition, it is appreciated that the figures providedherewith are for explanation purposes to persons ordinarily skilled inthe art and that the drawings are not necessarily drawn to scale.

The disclosure particularly describes a vacuum system with a filtercleaning device. The present disclosure describes how filter cleaningdevice may be used to clean debris from a vacuum filter without removalof the filter from the vacuum.

Turning now to FIG. 1, a perspective view of a vacuum is shown. Thevacuum 10 includes a debris canister 14. The debris canister may begenerally cylindrical with a closed bottom and with an open top side. Alid 18 attaches to the top of the canister to close the canister and toprovide a mounting location for various other parts of the vacuum. Thevacuum 10 may not include a vacuum motor as shown and may be used as avacuum separator in combination with another vacuum. The device 10,however, may also include a vacuum motor and operate independently as avacuum as shown in following figures. Typically, the vacuum motor wouldbe attached to the center of the lid 18 and would draw air out of thecanister through the center of the lid.

The lid 18 may be formed as a single piece. The lid 18 may include otherattached structures such as a cover portion 22. The cover 22 is used toattach a gasket 26 to the lid 18. The gasket 26 is used to seal around avacuum source such as a vacuum hose as discussed herein. The lid 18typically includes one or more latch tabs 30 which extend downwardlyfrom the lid to engage the canister 14 and secure the lid to thecanister. If desired, the lid 18 may include various mounting bosses 34for storing vacuum cleaning attachments or accessories such as a vacuumhose adapter 36.

The lid 18 includes mounting brackets 38 which allow a filter strikersuch as handle 42 to be attached to the lid. The handle 42 is pivotablymounted to the lid 18 via the mounting brackets 38. The handle 42 maymove between a first position where the handle rests against the lid 18as shown and a second position where the handle is pivoted up away fromthe lid to carry the vacuum 10. A torsion spring 46 is attached to a lidmounting bracket 38 and the handle 42. The torsion spring biases thehandle 42 against the lid 18 in the position shown in FIG. 1. The handle42 may be pivoted upwardly such as when carrying the vacuum 10. Thehandle 42 may be released, upon which the spring 46 causes the handle 42to forcefully strike the lid 18. FIG. 2 shows a perspective view of thevacuum 10 which is similar to that of FIG. 1. The vacuum 10 has beenrotated in FIG. 2, providing an additional view of the handle 42.

A vacuum separator without a vacuum motor may be used in combinationwith a vacuum source such as a vacuum to provide additional filtration.The gasket 26 has a hole 50 formed in the center which is sized toreceive a vacuum suction hose from another vacuum. The suction hose fromanother vacuum (not shown) is placed into the hole 50, drawing air frominside of the canister 14. The lid 18 includes an inlet hole 54. Theinlet hole 54 is sized to receive a vacuum hose which is used by aperson to draw debris into the canister 14. Air is drawn through theinlet vacuum hose and into the canister 14 via hole 54, through afilter, and out of the canister via hole 50. The filter separates dustand debris from the air and retains the debris in the canister 14. Ifthe vacuum 10 were formed as a stand-alone vacuum, a vacuum motor wouldtypically be attached to the center of the lid 18. In this situation,the gasket 26 and hole 50 may not be necessary and the motor would drawair through the filter and out of the canister 14.

Turning now to FIG. 3 another perspective view of a portion of thevacuum of FIG. 1 is shown. FIGS. 3 through 5 show views of the vacuum 10from the bottom with the canister 14 and other various structuresremoved. The lid 18 may be formed with a cylindrical collar 58 extendingdownwardly therefrom. The collar 58 is disposed in alignment with thegasket 26 and the outlet hole 50. The collar 58 has a hole 62 formed inthe bottom thereof and forms an air passage to the hole 50, allowing airto be drawn therethrough. The collar 58 may receive the rigid tubetypically found on the end of a vacuum hose and be used to stabilize thevacuum hose which is used to provide suction to the vacuum separator 10and draw air therethrough.

The lid 18 may also be formed with a filter mounting collar 66. Thefilter mounting collar extends downwardly from the bottom of the lid 18and provides a location to mount a vacuum filter. A filter is insertedover the filter mounting collar 66 and secured thereto. The lid 18 mayalso include mounting brackets 70 for a spark arrestor or debris guard.Mounting brackets 70 are attached to the bottom of the lid 18 in acircle around the outside of the filter mounting collar 66. The lid 18may include an air diverter 74 mounted below the air inlet hole 54. Theair diverter 74 directs the incoming air in a circular pattern in thecanister 14, helping to drop larger particles out of the air stream andkeep the filter cleaner.

Turning now to FIG. 4, another perspective view of a portion of thevacuum of FIG. 1 is shown. FIGS. 4 and 5 are similar to FIG. 3, but showadditional parts. A cylindrical filter 78 has been attached to the lid18 via filter mounting collar 66. The filter 78 is a rigid filter,rather than being a soft bag-type filter. Typically, the filter 78 maybe a cylindrical filter with pleated filter media. The filter 78includes a pleated filter media such as a filter paper or a syntheticfilter media and rubber top and bottom mounting rings. The filter mediaforms the sides of the cylindrical filter 78. The top and bottom ends ofthe filter 78 are used to secure the filter 78 to the lid 18. A sparkarrestor 82 or debris guard has also been attached to the lid 18 viamounting brackets 70. The spark arrestor 82 is cylindrical in shape andincludes a rigid circular top mounting ring 86, a rigid circular bottomplate 90 and a cylindrical guard 94 which forms the side walls of thespark arrestor. The guard 94 is mounted between the top ring 86 and thebottom plate 90. The top ring 86 has a hole through its center, allowingthe spark arrestor/guard 82 to be mounted over the filter 78. The topring 86 is formed with retaining structures which allow the sparkarrestor/guard 82 to be attached to the mounting brackets 70. Thecylindrical guard 94 may be made of metal mesh or metal screen andallows air to pass therethrough.

Air passes through the metal mesh 94 and then through the filter 78.Large pieces of debris are stopped by the metal mesh and kept fromhitting the filter. This is particularly useful where the vacuum 10 isused for cleaning ash from a fireplace or the like. While pieces ofinert debris will not typically harm a filter 78, small embers which arestill burning may burn the filter. The spark arrestor 82 will keep theseaway from the filter 78 to prevent damage to the filter.

The spark arrestor bottom plate 90 has a number of holes 98 formedtherethrough. The holes 98 are formed in a circular pattern adjacent theouter circumference of the bottom plate 90. The holes 98 allow debris tofall from the filter 78 and out of the spark arrestor. The bottom plate90 may also be used to retain the filter 78; securing the filter 78 tothe lid 18. As such, the bottom plate 90 may include a collar orindented portion 102 which engages the bottom rubber mounting ring ofthe filter 78. The spark arrestor top ring 86 includes mounting tabswhich engage the mounting brackets 70. Once a filter 78 is placed on thelid 18, the spark arrestor 82 is placed over the filter and rotated toengage the top ring tabs and the mounting brackets 70 and lock the sparkarrestor and filter in place. FIG. 5 shows the complete spark arrestor82 while FIG. 4 shows the outline of the spark arrestor screen 94 only,allowing the filter 78 to be seen through the spark arrestor.

As shown, the holes 98 are approximately one quarter of an inch wide andapproximately one half of an inch long, and approximately 18 holes aredisposed around the outer circumference of the bottom plate. The holes98 provide a near continuous annular opening around the outercircumference of the bottom plate 90, allowing good evacuation of debrisfrom the filter when cleaning the filter. Since the holes 98 provide atotal area which is much less than the open area of the spark arrestorscreen 94, most of the airflow through the spark arrestor 82 while thevacuum is in operation is through the screen 94 and not through theholes 98. The holes 98 are located below the pleated filter media sidesof the filter 78, allowing debris to fall from the filter 78 and out ofthe spark arrestor/guard 82.

Turning now to FIGS. 6 and 7, additional perspective views of the vacuumof FIG. 1 are shown. The vacuum 10 is shown from the side. FIG. 6 showsthe handle 42 in a lowered position while FIG. 7 shows the handle in apartially elevated position. The handle 42 is used for cleaning thefilter in addition to carrying the vacuum 10. As discussed, the handle42 is biased by a spring 46 to rest against the lid 18 in the positionshown in FIG. 6. The spring 46 may press the handle against the lid 18.

In order to clean the filter 78 and spark arrestor screen 94, the handle42 is lifted into a vertical position (as shown in FIG. 7 or movedfurther beyond the position shown into a completely vertical position)and released. The spring 46 moves the handle 42 quickly towards the lid18 and the handle forcefully strikes the lid 18. The shock of the handle42 striking the lid 18 dislodges debris from the filter 78 and the sparkarrestor screen 94, allowing the debris to fall into the canister 14.The holes 98 in the spark arrestor bottom plate 90 allow debris from thefilter to fall in to the canister. The debris falls off of the filter 78and through the holes 98. Cleaning the filter 78 with the handle 42works best when the vacuum 10 (or separate vacuum attached thereto) isturned off and air is not being drawn through the filter 78.

A performance advantage in cleaning the filter may be obtained by havinga rigid lid 18 (typically made of plastic), a rigid filter 78, and byhaving the filter 78 rigidly connected to the lid 18. This combinationoften transfers more momentum and a sharper impact to the filter 78 fromthe handle 42. The handle 42 is typically formed from a plastic such asa polyolefin which withstands repeatedly striking the lid 18.

Turning now to FIGS. 8 through 13, another vacuum 10 is shown. Thevacuum 10 is similar to the vacuum 10 of FIG. 1 but includes a vacuummotor. The vacuum of FIGS. 8 through 13 includes the parts, structures,features, and functionality of the vacuum discussed with respect toFIGS. 1 through 7 except where mentioned to the contrary. FIG. 8 shows apartially exploded view of the vacuum 10. FIG. 9 shows a top view of thetop portion of the vacuum including the motor and filter. FIG. 10 showsa bottom view of the top portion of the vacuum. FIG. 11 shows anotherbottom view of the top portion of the vacuum having the spark arrestorand filter removed. FIG. 12 shows a side view of the top portion of thevacuum having the handle removed. FIG. 13 shows another side view of thevacuum having the handle in an elevated position.

The vacuum 10 includes a cylindrical canister 14 which has a bottom, acylindrical side wall, and an open top side and a lid 18 which attachesto the top of the canister. The lid 18 typically includes one or morelatch tabs 30 which extend downwardly from the lid to engage thecanister 14 and secure the lid 18 to the canister 14. If desired, thelid 18 may include various mounting bosses 34 for storing vacuumcleaning attachments or accessories such as a vacuum hose adapter 36.

The lid 18 includes a handle 42 which is pivotably mounted to the lid18. The handle 42 may move between a first position where the handlerests against the lid 18 as shown and a second position where the handleis pivoted up away from the lid to carry the vacuum 10. A torsion spring46 is attached to the lid 18 and the handle 42. The torsion spring 46biases the handle 42 against the lid 18 in the position shown in FIG. 8.FIG. 11 shows the vacuum 10 with the handle 42 in an elevated position.The handle 42 may be pivoted upwardly such as when carrying the vacuum10. The handle 42 may be released, upon which the spring 46 causes thehandle 42 to forcefully strike the lid 18.

The lid 18 is provided with a vacuum motor 106 which may often bemounted beneath a cover or inside of the lid. Although not shown forclarity, the vacuum motor 106 typically includes a motor, fan, housing,etc. as necessary to move air through the vacuum 10. A cord 110 andswitch 114 may be provided to supply power to the vacuum motor 106 andto allow a user to control the operation of the vacuum motor 106. Acollar 52 defining an air inlet hole 54 is sized to receive a vacuumhose 118 which is used by a person to draw debris into the canister 14.Air is drawn through the vacuum hose 118, into the canister 14 via hole54, through a spark arrestor 82 and/or filter 78, and out of thecanister via the vacuum motor 106. The vacuum motor 106 may direct theair through exhaust vents 122 formed in the lid 18.

The top view of FIG. 9 better illustrates the positioning of the variousmounting bosses 34, the collar 52, and handle 42. The motor 106 islocated adjacent the center of the lid 18 and the handle 42 extendsaround the motor. The handle 42 is attached to mounting brackets 38which may be positioned on the sides of the motor 106 or formed as partof a motor housing. The handle 42 is pivotably mounted to the mountingbrackets 38 and typically includes one or more springs 46 which interactwith the brackets 38 (or housing) and handle 42 to bias the handleagainst the lid 18.

FIG. 10 illustrates the bottom of the lid 18. The collar 52 and inlethole 54 are connected to an air diverter 74 which directs air into thecanister 14 as desired. The air diverter 74 often directs the airtangentially into the canister 14 so that the air rotates within thecanister and particles are deposited into the canister 14 moreefficiently.

The vacuum 10 may include a debris guard/spark arrestor 82 whichsurrounds the filter 78. A debris guard 82 may prevent large objectsfrom hitting the filter 78. A spark arrestor 82 may similarly preventsparks from hitting the filter 78 if the vacuum 10 is intended to beused to collect ash from a fireplace. The guard/spark arrestor 82 istypically cylindrical in shape and may include a top mounting ring 86,bottom plate 90, and cylindrical guard screen 94 which forms the sidewalls of the spark arrestor and which is mounted between the top ring 86and the bottom plate 90. The screen 94 in FIG. 10 is shown transparentto allow for increased visibility of surrounding structures. Thecylindrical guard screen 94 is often made of a fine mesh metal screenwhich prevents larger particles from contacting the air filter 78. Thespark arrestor bottom plate 90 has a number of holes 98 disposed aroundits circumference. The holes 98 are disposed in a circle ofapproximately the same diameter as the filter media forming the sidewalls of the filter 78. The holes 98 allow debris to fall from thefilter 78 and out of the spark arrestor 82; particularly when the filteris cleaned. These holes may often be between about 0.1 and 0.3 incheswide and between about 0.1 and 1 inches long, and may be between about0.2 and 0.25 inches wide and between about 0.4 and 0.6 inches long. Theholes 98 may be sized such that most of the air flow is through thescreen 94 and not through the holes while allowing debris to fallthrough the holes 98 without significant obstruction. The bottom plate90 may also be used to retain the filter 78. As such, the bottom plate90 may include a collar or indented portion 102 which engages the bottomof the filter 78.

The holes 98 may approximately one quarter of an inch wide andapproximately one half to three quarters of an inch long, andapproximately 15 to 20 holes may be disposed around the outercircumference of the bottom plate. The holes 98 provide a nearcontinuous annular opening near the outer circumference of the bottomplate 90, allowing good evacuation of debris from the filter. Since theholes 98 provide a total area which is much less than the open area ofthe spark arrestor screen 94, most of the airflow through the sparkarrestor while the vacuum is in operation is through the screen 94 andnot through the holes 98.

The spark arrestor top mounting ring 86 has a hole through its center,allowing the spark arrestor 82 to be placed over a filter 78. The topmounting ring 86 is formed with retaining structures such as laterallyprotruding tabs which allow the spark arrestor/guard 82 to be attachedto the mounting brackets 70. The top mounting ring 86 may includelaterally protruding tabs which are captured by the mounting brackets 70when the spark arrestor 82 is placed against the bottom side of the lid18 and rotated to engage the tabs with the brackets 70.

FIG. 11 shows a bottom view of the lid 18 with the filter 78 and sparkarrestor 82 removed. The lid 18 may be formed with a filter mountingcollar 66 or other structure to locate and retain the filter 78 in theposition shown in FIG. 10. The filter 78 is mounted to the bottom of thelid 18 so that air must pass through the filter 78 to exit the vacuumcanister 14. The filter is attached to the filter mounting collar 66 andsecured to the lid 18. The filter 78 is often cylindrical and generallyrigid rather than being a soft, bag-type filter. The filter 78 oftenincludes a pleated filter media forming a cylindrical side wall, arubber bottom plate attached to the filter media, and a rubber top ringattached to the filter media which allows the filter to be mounted tothe vacuum. The rubber top ring typically has a hole through the centerthereof to allow air to flow out of the filter.

The lid 18 may also include three or more mounting brackets 70 forsecuring a spark arrestor or debris guard 82 to the lid. The sparkarrestor top mounting ring 86 interacts with the mounting brackets 70 tosecure the spark arrestor 82 to the lid 18. Often, the spark arrestor 82is placed against the lid with tabs located between the brackets 70 andthe spark arrestor is then rotated to lock the spark arrestor in placeby engaging the tabs with the brackets 70. The spark arrestor 82 is thusdisposed over the filter 78 to enclose and protect the filter. The sparkarrestor 82 is often used to secure the filter 78 to the vacuum lid 18.

Air passes into the vacuum 10 through the hose 18 and into the canister14. The air passes through the metal mesh screen 94 and then through thefilter 78, motor inlet hole 126, and out of the vacuum 10. Large piecesof debris are stopped by the metal mesh and kept from hitting thefilter. This is particularly useful where the vacuum 10 is used forcleaning ash from a fireplace or the like. While pieces of debris willnot typically harm a filter 78, small embers which are still burning mayburn the filter. The spark arrestor 82 will keep these away from thefilter 78 to prevent damage to the filter.

FIG. 12 shows a side view of the vacuum lid 18 with the handle 42removed. The spring 46 and handle pivot hole 128 can be more easilyseen. The handle pivot hole 128 is typically formed by a bracket 38 oras part of the motor housing. The handle 42 is received into the pivothole 128 such that the handle 42 can lay flat against the vacuum lid 18or can be elevated upwardly to carry the vacuum. The spring 46 istypically a rotary spring which may be coiled around a portion of thehandle 42 and which engages the handle 42 and the lid 18. The spring 46biases the handle towards the lid 18. The spring 46 causes the handle toforcefully strike the lid 18 if the handle 42 is lifted away from thelid 18 and released.

FIG. 13 shows a similar side view which shows the handle 42 disposed inan elevated position. The handle 42 is used for cleaning the filter inaddition to carrying the vacuum 10. As discussed, the handle 42 isbiased by a spring 46 to rest against the lid 18 in the position shownin FIG. 8. In order to clean the filter 78 and spark arrestor screen 82,the handle 42 is lifted into a vertical position as shown in FIG. 12 andreleased. The spring 46 moves the handle 42 quickly towards the lid 18and the handle 42 forcibly strikes the lid 18. The shock of the handle42 striking the lid 18 dislodges debris from the filter 78 and the sparkarrestor screen 94, allowing the debris to fall into the canister 14.Debris from the spark arrestor screen 94 may directly fall into thecanister 14. Debris from the filter media falls from the filter 78,through the holes 98 and into the canister 14. The holes 98 in the sparkarrestor bottom plate 90 allow debris from the filter to fall throughthe holes 98 and into the canister 14 without significant impediment.Filter cleaning works best when the vacuum 10 is turned off and air isnot being drawn through the filter 78.

It has been determined that, for many types of jobs, a canister vacuum10 will typically lose flow from a dirty filter 78 long before thecanister 14 needs to be emptied. This is particularly true where dust isbeing collected into the vacuum 10. Rather than removing the lid 18 fromthe vacuum canister 14, removing a filter 78, and cleaning or replacingthe filter, a user may simply lift the handle 42 and release the handleto cause the handle to strike the lid and remove debris from the filter.The user may do this several times quickly if desired and resume use ofthe vacuum 10. When a job is completed, the user may remove and replaceor clean the filter 78.

The examples are advantageous as they allow the filter 78 to be cleanedeasily without removing the filter from the vacuum 10 or otherwiseopening the vacuum canister 14. This avoids the time loss of opening thevacuum and manually cleaning the filter and avoids the mess that oftenoccurs while opening the vacuum and removing the filter. The filter canbe cleaned very easily and quickly on location. It is furtheradvantageous that the carrying handle 42 used to carry the vacuum 10 isalso used to strike the lid 18 and clean the filter 78. This allows aperson to carry the vacuum 10 and release the handle 42 from a verticalposition when setting the vacuum down and clean the filter without anyadditional effort. The ease of cleaning the filter 78 means that thefilter can be cleaned frequently during use of the vacuum 10 andperformance of the vacuum is maintained.

The present invention is also advantageous in providing a spark arrestor(debris guard) 82 which has a screen 94 forming the circumferential wallof the arrestor and which has holes in the bottom of the spark arrestorto allow debris to fall out of the spark arrestor while cleaning thefilter 78. The spark arrestor 82 may also serve as the attachment devicefor holding the filter 78 to the vacuum lid 18 (and thus the vacuum 10).Thus, a filter attachment device is provide which fits over the filterand generally encloses the filter and which also provides both acircumferential screen extending around the sides of the filter in aposition which is adjacent and generally parallel to the pleated filtermaterial and holes around the bottom of the attachment device which arenot covered by a screen but which are open to allow debris to passtherethrough. This arrangement protects the filter from sparks orembers, for example, but allows debris to fall off of the filter and outof the attachment device while cleaning the filter.

The above description of illustrated examples of the present invention,including what is described in the Abstract, are not intended to beexhaustive or to be limitation to the precise forms disclosed. Whilespecific examples of the invention are described herein for illustrativepurposes, various equivalent modifications are possible withoutdeparting from the broader scope of the present claims. Indeed, it isappreciated that specific example dimensions, materials, voltages,currents, frequencies, power range values, times, etc., are provided forexplanation purposes and that other values may also be employed in otherexamples in accordance with the teachings of the present invention.

What is claimed is:
 1. A vacuum comprising: a cylindrical canister forreceiving and holding debris, the canister having enclosed bottom andsides and having an opening on a top thereof; a lid attached to the topof the canister, the lid being disposed to cover the opening and closethe canister; a rigid cylindrical filter attached to a bottom of the lidsuch that the filter is disposed inside of the canister; an inlet portwhich receives a vacuum hose to allow debris to be collected in thecanister; a vacuum motor attached to the lid, the vacuum motor drawingair into the canister through the inlet port and drawing the air throughthe filter and out of the canister; a striking lever pivotably attachedto the lid; and a spring attached to the striking lever and to the lid,the spring biasing the striking lever against the lid such that a usermay release the striking lever from a vertical position to cause thestriking lever to forcefully strike the lid and thereby dislodge debrisfrom the filter and deposit the debris in the canister.
 2. The vacuum ofclaim 1, wherein the striking lever is a vacuum carrying handle.
 3. Thevacuum of claim 2, wherein the carrying handle is movable between agenerally horizontal storage position wherein the carrying handle restsagainst the lid and a generally vertical carrying position whereby auser may carry the vacuum with the carrying handle, and whereinreleasing the carrying handle from the carrying position causes thecarrying handle to forcefully strike the lid.
 4. The vacuum of claim 1,further comprising a debris guard mounted to the bottom of the lid suchthat the debris guard encloses the filter.
 5. The vacuum of claim 4,wherein the debris guard is generally cylindrical and has bottom plateand a cylindrical side wall, wherein the side wall comprises a screen,the screen being disposed laterally around sides of the filter, andwherein the bottom plate has holes formed therein beneath a lateralperimeter of the filter, the holes allowing debris to fall from thefilter and exit the spark arrestor.
 6. The vacuum of claim 1, furthercomprising a vacuum hose attached to the inlet port.
 7. A vacuumcomprising: a canister for receiving and holding debris, the canisterhaving an opening on a top thereof; a lid attached to the top of thecanister; a filter attached to a bottom of the lid such that the filteris disposed inside of the canister; an inlet port which allows debris tobe collected in the canister; an exhaust port which allows air to exitthe canister; a striking lever pivotably attached to the lid; and aspring attached to the striking lever and to the lid, the spring biasingthe striking lever towards the lid such that a user may release thestriking lever from an elevated position to cause the striking lever toforcefully strike the lid and thereby dislodge debris from the filterand deposit the debris in the canister.
 8. The vacuum of claim 7,wherein the filter is rigid.
 9. The vacuum of claim 7, furthercomprising a vacuum motor attached to the lid, the vacuum motor movingair into the canister through the inlet port, through the filter, andout of the canister through the exhaust port.
 10. The vacuum of claim 7,wherein the striking lever is a vacuum carrying handle.
 11. The vacuumof claim 10, wherein the carrying handle is movable between a generallyhorizontal storage position wherein the carrying handle rests againstthe lid and a generally vertical carrying position whereby a user maycarry the vacuum with the carrying handle, and wherein releasing thecarrying handle from the carrying position causes the carrying handle toforcefully strike the lid.
 12. The vacuum of claim 7, further comprisinga debris guard mounted to the bottom of the lid such that the debrisguard encloses the filter and such that air must flow through the debrisguard to flow through the filter.
 13. The vacuum of claim 12, whereinthe debris guard is generally cylindrical and has bottom plate and acylindrical side wall, wherein the side wall comprises a screen, thescreen being disposed laterally around sides of the filter, and whereinthe bottom plate has holes formed therein beneath a lateral perimeter ofthe filter, the holes allowing debris to fall from the filter and exitthe spark arrestor.
 14. A method for cleaning a vacuum filtercomprising: providing a vacuum having: a canister for receiving andholding debris, the canister having an opening on a top thereof; a lidattached to the top of the canister; a filter attached to a bottom ofthe lid such that the filter is disposed inside of the canister; an airinlet disposed in communication with the canister to allow air anddebris to be drawn into the canister, through the filter, and out of thevacuum; a striking lever pivotably attached to the lid; and a springbiasing the striking lever towards the lid; pivoting the striking leveraway from the canister lid; and releasing the striking lever such thatthe striking lever forcibly strikes the canister lid to thereby knockdebris from the filter and deposit the debris in the canister.
 15. Themethod of claim 14, wherein the filter is rigid.
 16. The method of claim14, wherein the striking lever is a vacuum carrying handle.
 17. Themethod of claim 16, wherein the method more specifically comprisescarrying the vacuum by the handle and then releasing the handle from anelevated position to allow the handle to forcibly strike the canisterlid.
 18. The method of claim 14, wherein the vacuum further comprises adebris guard mounted to the bottom of the lid such that the debris guardencloses the filter, wherein the debris guard is generally cylindricaland has bottom plate and a cylindrical side wall, wherein the side wallcomprises a screen, the screen being disposed laterally around thefilter, and wherein the bottom plate has holes formed therein beneath alateral perimeter of the filter, the holes allowing debris to fall fromthe filter and exit the spark arrestor.
 19. The vacuum of claim 14,wherein the vacuum further comprises a vacuum motor attached to the lid,the vacuum motor moving air into the canister through the inlet port,through the filter, and out of the canister through an exhaust port.